SIK2-IN-4 (Compound 4) is a highly selective SIK1/2 inhibitor (IC50s 0.143 and 0.076 µM, respectively). SIK2-IN-4 reduces the phosphorylation of transcription coactivator 3 (CRTC3) by targeting SIK1/2, thereby regulating cAMP response element binding protein (CREB)-dependent transcriptional activity. SIK2-IN-4 inhibits the production of pro-inflammatory cytokines such as TNF (IC50: 0.11 µM), IL-12/23 p40 (IC50: 0.25 µM), and IL-23 (IC50: 0.47 µM), while inducing the expression of the anti-inflammatory cytokine IL-10. SIK2-IN-4 can be used to study intestinal inflammation and other chronic inflammatory diseases[1].